The subject matter disclosed herein generally relates to turbine engines and, more particularly, to a fuel injection assembly for use in a turbine engine.
At least some known turbine engines are used in cogeneration facilities and power plants. Such engines may have high specific work and power per unit mass flow requirements. To increase the operating efficiency, at least some known turbine engines, such as gas turbine engines, operate with increased combustion temperatures. In at least some known gas turbine engines, engine efficiency increases as combustion gas temperatures increase.
However, operating with higher temperatures may also increase the generation of polluting emissions, such as oxides of nitrogen (NOX). In an attempt to reduce the generation of such emissions, at least some known turbine engines include improved combustion system designs. For example, many combustion systems may use premixing technology that includes tube assemblies or micro-mixers that facilitate mixing substances, such as diluents, gases, and/or air with fuel to generate a fuel mixture for combustion.
However, the benefits of such combustion systems may be limited. Each tube assembly or micro-mixer has a substantially large recirculation region within its center area or large blockage area. More specifically, the combustion product that is recirculating in the center area interacts with the combustible mixture within each of the tubes in the tube assemblies that are located within the center area. As a result, the temperature within the recirculation region is substantially higher than other areas of the tube assembly or micro-mixer. The high temperature results in a reduced margin of a flashback and/or a flameholding in the tubes that are located in the recirculation region. Increased temperatures may also increase the wear of the combustor and its associated components, and/or may shorten the useful life of the combustion system.